1. Field of the Invention
This invention relates to a new system for efficient delivery of information and a method of providing efficient information delivery.
2. Prior Art
There are a number of current and proposed systems which allow information to be associated with a location. Some of these systems provide the location in terms of spatial co-ordinates using GPS (the satellite-based Global Positioning System) or cellular radio technologies (such as Cursor from Cambridge Positioning Systems Ltd.). Other systems provide the location in terms of proximity to one of a number of devices which are positioned on objects or in particular locations. Each such beacon device (“beacon”) has a local communication means which allows it to pass information to client devices in the vicinity. This invention relates to this latter class of systems.
One difficulty with systems using a beacon is providing a means to update the information which it delivers. One approach is to give the beacon a communication system capable of connecting to a central network which allows it to retrieve and store information in integral storage. This results in a bulky, expensive device which consumes a considerable amount of power. For example, StreetBeam Inc. offer a Remote Access Mobile Point (RAMP), which is updated wirelessly, uses infrared to deliver information and is housed in a large, custom-built advertising panel.
The alternative is to store on the beacon, and transmit, only a reference to the required information and to rely on any network communication system of the client devices to map this reference to the desired information, and retrieve that information (see, for example, WO01/44831). This allows the beacon to be made very much smaller, cheaper and with very low power consumption. However, the client device then assumes both the cost and delay associated with retrieving the information.
In communication systems, it is common to use local caches to reduce the traffic on the central network and therefore reduce the associated cost and delay of information delivery. For example:
Web Browsers use a cache to store recently downloaded web pages.
Network cache servers allow multiple users to share one cache, thus reducing the amount of network traffic.
WideRay from WideRay Corporation is a network-connected beacon which caches the information which it transmits.
In all of these systems, the cache sits between the client and a central network and needs significant storage capacity to hold the variety of retrieved information.